This invention relates to a fuel feed device for an internal combustion engine and more particularly to an improved arrangement for supplying fuel and a control therefor under transient conditions.
A wide variety of charge forming systems have been employed for internal combustion engines for supplying their fuel requirements. Such fuel supply systems include carburetors and fuel injectors. Fuel injectors may, in many instances, provide better control for the amount of fuel supplied to the engine, particularly during cycle to cycle operation. However, regardless of the charge forming device employed, the most difficult conditions to satisfy for engine running are transient conditions. That is, when the engine speed or load is changed, the change in fuel requirements of the engine are difficult to accommodate. Although various devices have been employed for providing the appropriate amount of fuel for transient conditions, these systems all have some defects.
For example, a particularly troublesome transient condition is under acceleration. This problem is particularly acute in conjunction with two cycle engines and particularly those wherein the fuel is introduced to the crankcase chamber of the engine before it is delivered to the combustion chamber. When the engine is accelerated, quantities of fuel which may have been accumulated in the induction system will be drawn into the combustion chamber and, coupled with the supply of additional fuel to meet acceleration conditions, cause poor running. This problem is particularly acute when the engine has been operating for a long period of time at a low engine speed and then is accelerated. This condition is particularly prevalent in connection with outboard motors wherein an engine may operate at a low speed for trolling for long periods of time and then be accelerated suddenly.
It is, therefore, a principal object of this invention to provide an improved fuel feed device for an internal combustion engine.
It is a further object of this invention to provide an improved arrangement for controlling the supply of fuel to an engine during acceleration after the engine has been operated at low speeds for long periods of time.
It is a further object of this invention to provide an improved fuel injection system for an internal combustion engine.
It is a further object of this invention to provide an improved fuel injection system for an internal combustion engine, and particularly one operating on the two-stroke crankcase compression principle.